MICROBIOLOGICAL ASSESSMENT OF WATERMELON FROM MARKETS IN BENIN CITY, NIGERIA
Authors: * Mezue S.S, Aghimien M
In this study, samples of watermelon (Citrullus lanatus) were obtained from different locations (Oba market, Uselu market and New Benin Market) in Benin City, Edo State Nigeria, to examine their microbiological deterioration when stored at room (22oC) and refrigerator temperature (4oC) for 5 days. Isolation and identification of the microbial species present in the samples were performed using cultural, morphological and biochemical characteristics. The bacterial counts ranged from 2.7×104 CFU/ml to 6.87×104 CFU/ml and 1.23×104 CFU/ml to 2.87×104 CFU/ml, at 22oC and 4oC respectively. On the other hand the fungal counts ranged from 1.17×104 CFU/ml to 2.77×104 CFU/ml and 1.93×104 CFU/ml to 4.00×104 CFU/ml at 4oC and 22oC respectively. The microbial load was significantly reduced (P < 0.001) at refrigerator temperature compared with sample storage at room temperature. The microbial isolates identified were Enterobacter aerogenes, Bacillus subtilis, Pseudomonas aeruginosa, Lactobacillus fermenti, Staphylococcus aureus, Aspergillus niger, Saccharomyces cerevisiae, Fusarium oxysporum, Rhizopus stolonifer, and Mucor sp. B. subtilis, P. aeruginosa, S. aureus and Mucor sp. were the most frequently isolated microbes at room temperature, while P. aeruginosa, B. subtilis and F. oxysporum had the highest frequency of occurrence at refrigerator temperature. The results obtained in this work suggest that proper storage temperature and sanitation could significantly influence the shelf-life and microbial diversity of freshly cut watermelon.
Affiliations: Department of Microbiology, Faculty of Life Sciences, University of Benin, PMB 1154, Benin City, Nigeria
Keywords: Contamination, Shelf-life, Room Temperature, Refrigerator Temperature, Watermelon
Published date: 2016/12/30